Highly recommend doing the iwire merge if you want a clean swap with everything working like out of the dealer lot. But if you are only making a dedicated track/rally car then doing the full swap isn't a bad idea. It is a lot of work and money to buy the right tools to do the job.
When I do swap my coupe I will be going with iwire merge bcoz i ain't got that kind of time and/or patience for basically everything Brian(? Getting old, forgetting things now a day lol) mentioned. If I ever get my computer up and running I will make a journal of the process.
Really good article. I came to the same conclusion when I did my swap. Even if you do all the work and make it fit perfect, I think the GD dash kind of seems out of place in a GC. The only thing I like better about the GD interior is the gauge cluster. But with a little bit of work you can make that fit pretty well in a GC.